I recently was pulling some components of a used board and ran into what i thought at first was a transistor. Testing with a meter i found a diode junction, but when i tested other lead combinations the diode junction switched to 0 ohms (both directions). After careful study, the diode switches to o ohms until you reverse the probes, then it goes back to being a diode again. Does anyone know what this is? Whatever stated it diode is in, it will not revert until the - probe is touched to the lead.